Not a lot of people know that:
Saint Valentine, officially Saint Valentine of Terni, is a widely recognized 3rd-century Roman saint commemorated on February 14 and since the High Middle Ages is associated with a tradition of courtly love.
All that is reliably known of the saint commemorated on February 14 is his name and that he was martyred and buried at a cemetery on the Via Flaminia close to the Ponte Milvio to the north of Rome on that day. It is uncertain whether St. Valentine is to be identified as one saint or the conflation of two saints of the same name. Several different martyrologies have been added to later hagiographies that are unreliable.
Because so little is reliably known of him, in 1969 the Catholic Church removed his name from the General Roman Calendar, leaving his liturgical celebration to local calendars. The Roman Catholic Church continues to recognize him as a saint, listing him as such in the February 14 entry in the Roman Martyrology, and authorizing liturgical veneration of him on February 14 in any place where that day is not devoted to some other obligatory celebration in accordance with the rule that on such a day the Mass may be that of any saint listed in the Martyrology for that day. Use of the pre-1970 liturgical calendar is also authorized under the conditions indicated in the motu proprio Summorum Pontificum of 2007. Saint Valentine’s Church in Rome, built in 1960 for the needs of the Olympic Village, continues as a modern, well-visited parish church.
Saint Valentine is commemorated in the Anglican Communion, as well as in Lutheranism. February 14 The Lutheran Service Book, with its penchant for the old Roman calendar, commemorates Valentine on this date. By some of the Eastern Orthodox Church, Saint Valentine the Presbyter of Rome is celebrated on July 6 and Hieromartyr Valentine (Bishop of Interamna, Terni in Italy) is celebrated on July 30. Notwithstanding, because of the relative obscurity of these two saints in the East and since there is no commemoration of St. Valentine in the Greek Orthodox Church, members of the Greek Orthodox Church named Valentinos (male) or Valentina (female) may observe their name day on the Western ecclesiastical calendar date of February 14.